1. Field of the Invention
This invention relates to a moving body detection device, and more particularly to a moving body detection device of a camera for automatically determining a moving body and photographing the same or automatically tracking a moving body and photographing the same.
2. Description of the Related Art
Conventionally, various types of moving body detection cameras for dividing a relatively large range of an image of the camera into a plurality of areas and determining one of the areas in which a moving body lies are developed. Particularly, when a moving object is photographed, the operator manually and rapidly specifies a small area of the image of the camera to determine the area of the moving body. Further, some cameras detect the gazing point or the moving body by detecting the line of sight of the operator.
For example, according to Japanese Patent Application No. H.2-235074 (corresponding to Japanese Patent Disclosure No. 4-114135), the technique relating to a measuring range finder selection device is disclosed. In a camera including a means for dividing an image plane into a plurality of areas and selecting one of the areas, a focus frame display means for displaying the selected area, and a focusing means for setting the focus on an object lying in the focus frame, the focus frame is constructed by a focus frame selection means, a resistance comparing means and a means for moving the display of the focus frame to detect the direction in which a desired focus frame lies, move the focus frame in the detected direction and display the same.
Further, in the Japanese Patent Disclosure No. H.3-177828, the technique for improving the line-of-sight detecting operation of a line-of-sight detection device is disclosed.
Further, in the Japanese Patent Disclosure No. H.2-96707, the technique relating to an exposure controlling device having a network which is operated by learning to output a signal indicating the main portion of an object when the pattern of the object is input, for selecting a signal of the main portion of the object from outputs of a plurality of photoelectric conversion elements according to the output from the network and detecting the focus based on the selected signal is disclosed.
Further, in the Japanese Patent Publication No. S.59-32743, a correlation tracking device for tracking an object by use of the correlation process is disclosed.
However, when the operator manually selects a desired area from a large area of the image plane in the image of the camera by use of a joy stick or the like, it is extremely difficult to rapidly select the desired area for an object which rapidly moves, thereby requiring skill.
In the method of line-of-sight detection, it is difficult to accurately select a desired area of the image plane.
When the main object is automatically recognized from a large area of the image plane in the image of the camera by use of a neural network or the like, a large number of candidates of the main object may be present, making it difficult to recognize the main object.
Further, when a moving body is detected, a large field of view is first selected and then a specified object is selected from the selected field, but the moving object cannot be accurately traced in the prior art if the movement of the camera and the target moving object are not separated.
Further, in the device disclosed in the Japanese Patent Publication No. S.59-32743, the detection range of a motion vector, that is, the shift amount of correlation calculation is 0, 1, - - - , N if the sampling time interval of two compared images is .DELTA.T and kept constant. Since time for the calculation .tau. becomes longer as the shift amount N is set to a larger value, it is preferable to set the shift amount to a small value. However, if the shift amount N is set to a small value, the detection range of the shift amount becomes narrow. If .DELTA.T is set short so as to make it possible to detect a rapidly moving object, it becomes impossible to detect a slowly moving object, and if .DELTA.T is set long so as to make it possible to detect a slowly moving object, it becomes impossible to detect a rapidly moving object.